Continuous fiber prepreg yarn production line for 3D printing

Abstract

The invention discloses a continuous fiber preimpregnated filament production line for 3D printing, which comprises a single screw extruder, a preimpregnation workbench, an impregnation mold, a sizing device and a winding device, a pay-off rack, a pay-off guide rack, a mold mounting position, a sizing position and a winding seat are sequentially arranged on the preimpregnation workbench according to the wiring direction of continuous fibers; the dipping mold is installed on the mold installation position, the sizing device is installed on the sizing position, the winding device is installed on the winding seat, a plurality of direction guide wheels for guiding paying-off are installed on the paying-off guide frame, a longitudinal S-shaped dipping flow channel is arranged in the dipping mold, and the longitudinal S-shaped dipping flow channel is communicated with the longitudinal S-shaped dipping flow channel. And when the dipping mold is fixed on the mold mounting position, a discharge port of the single-screw extruder is connected with the dipping mold, and a molten thermoplastic resin material can be extruded into the longitudinal S-shaped dipping runner. In this way, the continuous fiber internal infiltration uniformity can be remarkably improved, and the problem that a thermoplastic resin material is prone to aging is solved.

Description

Technical Field

[0001] The present invention relates to the field of 3D printing materials, and in particular to a production line for 3D printing continuous fiber prepreg. Background Art

[0002] In the independent extrusion type continuous fiber composite material FDM 3D printer, the printer is controlled by two independent nozzles, one of which is responsible for printing thermoplastic resin materials, and the other nozzle is responsible for printing prepregs made of continuous fibers such as carbon fiber, glass fiber and aramid fiber. At present, the preparation of continuous fiber impregnation usually adopts the method of transverse roller impregnation, which is difficult to generate a large pressure at the outlet mold. The thermoplastic resin material cannot effectively infiltrate into the inner layer structure of the continuous fiber within a limited time, resulting in poor impregnation effect of the continuous fiber prepreg. It is easy to break and plug during the use of 3D printing, which leads to printing failure. At the same time, when such continuous fiber prepreg is used as a 3D printing material, the strength of the final product will be difficult to achieve the designed effect. In addition, the existing prepreg preparation method is prone to the phenomenon of easy aging of thermoplastic resin materials during the preparation process. Therefore, it is necessary to optimize the existing production process route to further improve the preparation quality of continuous fiber prepreg. Summary of the invention

[0003] The main technical problem solved by the present invention is to provide a production line for continuous fiber prepreg yarns, which can increase the continuous fiber surface wetting depth and enhance the impregnation effect.

[0004] In order to solve the above technical problems, a technical solution adopted by the present invention is: to provide a continuous fiber prepreg production line for 3D printing, the 3D printing continuous fiber prepreg production line comprises: a single screw extruder, a prepreg workbench, an impregnation mold, a sizing device and a winding device, a pay-off frame, a pay-off guide frame, a mold mounting position, a sizing position and a winding seat are arranged on the table of the prepreg workbench in sequence according to the running direction of the continuous fiber, the impregnation mold is installed on the mold mounting position, the sizing device is installed on the sizing position, the winding device is installed on the winding seat, and a plurality of guides are installed on the pay-off guide frame. The guide wheel can guide the direction of the pay-off according to the requirements of the production line. A longitudinal S-shaped impregnation channel is provided in the impregnation mold. When the impregnation mold is fixed on the mold mounting position, the discharge port of the single-screw extruder is connected to the impregnation mold, and the molten material can be squeezed into the longitudinal S-shaped impregnation channel. The barrel of the continuous fiber is placed on the pay-off frame, and the continuous fiber led out from the barrel is guided into the impregnation mold by the guide wheel on the pay-off guide frame, and is led out from the outlet of the impregnation mold after being impregnated in the longitudinal S-shaped impregnation channel, and is then wound up by the winding device after being sizing by the sizing device.

[0005] In a preferred embodiment of the present invention, the prepreg workbench is a frame structure as a whole, which is spliced ​​by aluminum alloy profiles with mounting rails of the same specifications on four sides, including a workbench table, a wire pay-off frame and a wire pay-off guide frame. The workbench table is a rectangular frame formed by two long side columns of the same length and two short side columns of the same length vertically spliced ​​in pairs, and a plurality of load-bearing beams arranged parallel to the short side columns are installed in parallel in the middle of the rectangular frame, and the four corners of the table are respectively installed with foot columns of the same height; the wire pay-off frame includes a wire pay-off support and a wire pay-off rod, the wire pay-off support is vertically fixed at the middle position of the inner long side column, the wire pay-off rod is vertically fixed on the wire pay-off support, and the fixing direction of the wire pay-off rod is parallel to the load-bearing beam; the wire pay-off guide frame includes a first guide column, a second guide column and a guide beam, the first guide column and the second guide column have the same height, the second guide column is vertically fixed on the short side column on one side, the first guide column is fixed on the load-bearing beam close to the wire pay-off support, and the first guide column is fixed on the load-bearing beam close to the wire pay-off support. A cooling fan is installed on the column body, and the cooling fan faces the winding path of the continuous fiber, and the guide beam is fixed on the top of the first guide column and the second guide column, and a first guide wheel seat and a second guide wheel seat arranged in sequence along the pay-off direction are arranged on the beam body of the guide beam, a first guide wheel is installed on the first guide wheel seat, and a second guide wheel is installed on the second guide wheel seat, and two tension wheels are installed on the beam body on both sides of the second guide wheel, and the second guide wheel and the two tension wheels together form a tension adjusting wheel group; the left end head portion of the guide beam exceeds the end head of the first guide column, and the exceeding part is installed with a third guide wheel; the mold mounting position is arranged in the middle position of the second guide column, and the mold mounting position is installed with a mold mounting plate, and when the impregnation mold is fixed on the mold mounting plate, the impregnation mold is located as a whole on the outside of the prepreg workbench table, and the winding seat is arranged at the other end away from the mold mounting position, and the sizing position is arranged between the second guide column and the first guide column. The short side column directly below the impregnation mold is connected to the winding seat through a cross bar parallel to the long side column, the inner side of the cross bar is attached to the outer sides of the first guide column and the second guide column, and the sizing position is arranged on the cross bar, located between the first guide column and the second guide column. A wire winding adjustment structure is also provided between the sizing position and the winding seat, and the wire winding adjustment structure is composed of two adjustment rods fixed in parallel on the work surface between the first guide column and the winding seat, namely the first adjustment rod and the second adjustment rod, the first adjustment rod and the second adjustment rod are coplanar with the wire release guide frame, the first adjustment rod is installed with a fourth guide wheel, and the second adjustment rod is installed with a fifth guide wheel.

[0006] In a preferred embodiment of the present invention, a cartridge seat is provided below the mold mounting position, and the cartridge seat is fixed to the outside of the prepreg workbench and is located below the table top.

[0007] In a preferred embodiment of the present invention, the impregnation mold includes a cover plate, a mold body, a heating plate, an inlet pressure plate and an outlet pressure plate. The cover plate and the heating plate have the same size as the mold body. The cover plate is tightly pressed on the surface of the mold body by fastening bolts, and the heating plate is fixed to the back of the mold body by fastening bolts. A longitudinal S-shaped impregnation flow channel is provided on the surface of the mold body, and the inlet and outlet directions of the longitudinal S-shaped impregnation flow channel are perpendicular to each other and there are at least two continuous turns between the inlet and the outlet. A flange interface connected to the head of the single-screw extruder is provided on one side of the mold body, and the flange interface is connected to the The feed port arranged at the lower half of the longitudinal S-shaped immersion channel is through-connected, and the inlet and outlet of the longitudinal S-shaped immersion channel are respectively installed with an inlet pressure plate and an outlet pressure plate, the inlet pressure plate is provided with a sizing inlet hole, the outlet pressure plate is provided with a sizing outlet hole, a temperature sensor and a downflow hole connected to the outlet position of the longitudinal S-shaped immersion channel are provided at the bottom of the mold body, an upflow hole connected to the inlet position of the longitudinal S-shaped immersion channel is provided at the upper part of the mold body, and a top screw structure is further provided between the cover plate and the mold body, and the top screw structure includes an outer top screw hole on the cover plate and a corresponding inner top screw hole on the mold body.

[0008] A semi-enclosed slot positioning structure is provided between the mold body and the cover plate, and a bolt connection structure between the cover plate and the mold body is evenly arranged outside the semi-enclosed slot positioning structure, and the semi-enclosed slot positioning structure includes a semi-enclosed positioning groove provided on the mold body surface around the longitudinal S-shaped impregnation flow channel and a positioning convex strip provided on the cover plate that matches the positioning groove. A V-shaped positioning pin is installed at the outlet position of the longitudinal S-shaped impregnation flow channel, and the V-shaped positioning pin is composed of a pin rod and a pin head, and a V-shaped material bundle port is provided between the pin rod and the pin head.

[0009] In a preferred embodiment of the present invention, the sizing die includes a sizing die, a heating sleeve, a fan and an L-shaped bracket, the short side of the L-shaped bracket is fixed on the cross bar, the fan is installed at the lower part of the long side of the L-shaped bracket, the heating sleeve is fixed at the upper part of the long side of the L-shaped bracket, the sizing die is fixed in the middle of the heating sleeve, the upper part of the long side of the L-shaped bracket is provided with a corresponding die head avoidance area, the heating sleeve is installed with a heating rod and a temperature sensor, the heating rod is installed below the sizing die, and the temperature sensor is installed above the sizing die.

[0010] In a preferred embodiment of the present invention, the winding device includes a linear module, a stepper motor, a winding disk and a pressure block, the linear module is fixed on the winding seat, the stepper motor is installed on the linear module, and can move horizontally driven by the linear module, a transmission rod is installed at the power output end of the stepper motor, the winding disk is installed on the transmission rod, and the pressure block is installed on the top of the transmission rod to fix the winding disk on the transmission rod.

[0011] The beneficial effects of the present invention are as follows: First, the present invention optimizes the existing continuous fiber production prepreg production line, and changes the impregnation method on the production line to longitudinal S-shaped flow channel infiltration. In this way, when the continuous fiber passes through the S-shaped flow channel, it is equivalent to the impregnation roller in the traditional impregnation method. Through the extrusion effect at the S-shaped flow channel, the thermoplastic resin material is helped to better penetrate into the interior of the continuous fiber bundle, and at the same time, the air bubbles that may exist in the continuous fiber bundle are squeezed out, which helps to improve the quality of the interface bonding between the continuous fiber and the thermoplastic resin material, reduce the porosity in the composite material, and thus improve its mechanical properties. Secondly, removing the traditional impregnation roller is conducive to reducing the melting cavity volume of the impregnation mold and reducing material waste; and the S-shaped flow channel is arranged longitudinally, and an overflow hole is left at the bottom to prevent the thermoplastic resin material from staying in the flow channel for a long time, and to prevent the quality preparation of the continuous prepreg caused by material aging. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the overall structure of a preferred embodiment of the present invention;

[0013] Figure 2 is a schematic structural diagram of a prepreg workbench in the illustrated embodiment; Figure 3 is a schematic diagram of the structure of the dipping mold in the illustrated embodiment;

[0014] Figure 4 is a schematic structural diagram of a sizing device in the illustrated embodiment;

[0015] Figure 5 is a schematic structural diagram of a winding device in the illustrated embodiment;

[0016] The markings of the components in the accompanying drawings are as follows:

[0017] 1. Barrel, 2. Prepreg table, 3. Single screw extruder, 4. Dipping mold, 5. Sizing device, 6. Fan,

[0018] 7. Winding device, 8. Receiving barrel;

[0019] 201. Long side column, 202. Short side column, 203. Load-bearing beam, 204. Foot column, 205. Crossbar, 206. Wire support,

[0020] 207. Pay-off rod, 208. First guide column, 209. Second guide column, 2010. Guide beam, 2011. First guide wheel seat, 2012. Second guide wheel seat, 2013. First adjustment rod, 2014. Second adjustment rod, 2015. Winding seat, 2016. Bottom rod, 2017. Mold mounting plate, 2018. Barrel seat;

[0021] 401. Cover plate, 402. Mold body, 403. Heating plate, 404. Outlet pressure plate, 405. V-shaped positioning pin, 406. Temperature sensor, 407. Inlet pressure plate, 408. Fastening bolts, 409. Interface flange;

[0022] 4011. Positioning convex strip, 4012. Bolt connection outer hole, 4013. External top screw hole;

[0023] 4021. Longitudinal S-shaped impregnation channel, 4022. Feed hole, 4023. Internal top screw hole, 4024. Positioning groove,

[0024] 4025. Bolt connection inner hole, 4026. Downflow hole, 4027. Upflow hole; 4051. Pin head, 4052. Pin rod, 4053. Material bundle opening;

[0025] 501. sizing die, 502. heating sleeve, 503. L-shaped bracket, 504. fan, 505. fan bracket, 506. temperature sensor, 507. heating rod;

[0026] 701. Stepper motor, 702. Winding reel, 703. Press block, 704. Linear module. DETAILED DESCRIPTION

[0027] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0028] See also Figures 1 to 5 , the embodiment of the present invention includes:

[0029] A continuous fiber prepreg production line for 3D printing, the 3D printing continuous fiber prepreg production line comprising: a single screw extruder 3, a prepreg workbench 2, an impregnation mold 4, a sizing mold 5 and a winding device 7, the prepreg workbench 2 is provided with a pay-off frame, a pay-off guide frame, a mold mounting position, a sizing position and a winding seat 2015, the impregnation mold 4 is installed on the mold mounting position, the sizing device 5 is installed on the sizing position, the winding device 7 is installed on the winding seat 2015, a plurality of guide wheels are installed on the pay-off guide frame, the mold mounting position is arranged relying on the pay-off guide frame, a longitudinal S-shaped impregnation flow channel 4021 is provided in the impregnation mold 4, when the impregnation mold 4 is fixed on the mold mounting position, the discharge port of the single screw extruder 3 is connected to the impregnation mold 4, and the molten material can be squeezed into the longitudinal S-shaped impregnation flow channel 4021;

[0030] During processing, the continuous fiber barrel 1 is placed on the pay-off frame, and the continuous fiber drawn out from the barrel 1 is guided into the impregnation mold 4 by the guide wheel on the pay-off guide frame, and is drawn out from the outlet of the impregnation mold 4 after being impregnated through the longitudinal S-shaped impregnation channel 4021, and then is sizing treated by the sizing device 5 and then wound up by the winding device 7.

[0031] The prepreg workbench 2 is a frame structure as a whole, which is made of aluminum alloy 3030 profiles with mounting rails of the same specifications on four sides, including a workbench table, a wire-laying frame and a wire-laying guide frame. The workbench table is a rectangular frame formed by two long side columns 201 of the same length and two short side columns 202 of the same length vertically connected in pairs. Four load-bearing beams 203 arranged parallel to the short side columns are installed in parallel in the middle of the rectangular frame. The four corners of the table are respectively installed with the same height of the The pay-off frame is composed of a pay-off support column 206 and a pay-off rod 207. The pay-off support column 206 is vertically fixed to the middle position of the inner long side column 201. The pay-off rod 207 is vertically fixed to the pay-off support column 206. The fixing direction of the pay-off rod 207 is parallel to the load-bearing beam 203. The pay-off guide frame includes a first guide column 208, a second guide column 209 and a guide crossbeam 2010. The first guide column 208 and the second guide column 209 are high The second guide column 209 is vertically fixed on the short side column 202 on one side, the first guide column 208 is fixed on a load-bearing beam 203 close to the pay-off support column 206, a cooling fan 6 is installed on the column body of the first guide column 208, and the cooling fan 6 faces the winding path of the continuous fiber, the guide crossbeam 2010 is fixed on the top of the first guide column 208 and the second guide column 209, a first guide wheel seat 2011 and a second guide wheel seat 2012 arranged in sequence along the pay-off direction are arranged on the beam body of the guide crossbeam 2010, a first guide wheel is installed on the first guide wheel seat 2011, and a second guide wheel is installed on the second guide wheel seat 2012, two tension wheels are installed on the beam body on both sides of the second guide wheel seat, and the second guide wheel and the two tension wheels together form a tension adjustment wheel group, and the left end portion of the guide crossbeam 2010 exceeds the end of the first guide column 208, and the exceeding part is installed with a third guide wheel;

[0032] The mold mounting position is set in the middle position of the second guide column 209, and the mold mounting position is installed with a mold mounting plate 2017. When the impregnation mold 4 is fixed on the mold mounting plate 2017, the impregnation mold 4 is located as a whole on the outside of the table top of the prepreg workbench 2. The winding seat 2015 is arranged at the other end away from the mold mounting position, and the sizing position is arranged between the second guide column 209 and the first guide column 208.

[0033] The short side column 202 directly below the impregnation mold 4 is connected to the winding seat 2015 through a cross bar 205 parallel to the long side column 201, and the inner side of the cross bar 205 is attached to the first guide column 208 and the second guide column 209, and the sizing position is arranged on the cross bar 205 and is located between the first guide column 208 and the second guide column 209.

[0034] A wire-taking adjustment structure is also provided between the sizing position and the winding seat 2015, and the wire-taking adjustment structure is composed of two adjustment rods arranged in parallel and fixed on the table between the first guide column 208 and the winding seat 2015, namely the first adjustment rod 2013 and the second adjustment rod 2014, the first adjustment rod 2013 and the second adjustment rod 2014 are coplanar with the wire-releasing guide frame, the first adjustment rod 2013 is vertically fixed on a bottom rod 2016 connecting two load-bearing beams 203, the first adjustment rod 2014 is equipped with a fourth guide wheel, the second adjustment rod 2013 is vertically fixed on a load-bearing beam 203, and the second adjustment rod 2013 is equipped with a fifth guide wheel. The wire-taking adjustment structure can adjust the angle and tension of the impregnated continuous fiber entering the winding disk on the winding device 7, so that the entire winding action remains stable.

[0035] A barrel seat 2018 is provided directly below the mold mounting position, and the barrel seat 2018 is installed directly below the mold mounting position relying on the foot column 204 of the prepreg workbench 2, so that the receiving barrel 8 is placed on the barrel seat 2018 to prevent overflow from hanging directly on the ground, which is convenient for subsequent recycling.

[0036] The impregnation mold 4 includes a cover plate 401, a mold body 402, a heating plate 403, an inlet pressure plate 407 and an outlet pressure plate 404. The cover plate 401 and the heating plate 403 have the same size as the mold body 402. The cover plate 401 is pressed against the surface of the mold body 402 by fastening bolts 408. The heating plate 403 is fixed to the back of the mold body 402 by fastening bolts 408. A longitudinal S-shaped impregnation flow channel 4021 is provided on the surface of the mold body 402. The longitudinal S-shaped impregnation flow channel 4021 is composed of two consecutive turns of the same radius. The inlet and outlet directions of the longitudinal S-shaped impregnation flow channel 4021 are perpendicular to each other. A flange connection connected to the head of the single-screw extruder 3 is provided on one side of the mold body 402. The flange interface 409 is connected with the feed port 4022 arranged at the lower half of the longitudinal S-shaped impregnation channel 4021. The inlet and outlet of the longitudinal S-shaped impregnation channel 2021 are respectively installed with an inlet pressure plate 407 and an outlet pressure plate 404. The inlet pressure plate 407 is provided with a through sizing inlet hole, and the outlet pressure plate 404 is provided with a through sizing outlet hole. A V-shaped positioning pin 405 is installed at the outlet position of the longitudinal S-shaped impregnation channel 2021. The V-shaped positioning pin 405 is composed of a pin rod 4052 and a pin head 4051. A V-shaped bundle port 4503 is arranged between the pin rod 4502 and the pin head 4501. The continuous fiber after impregnation can be automatically shaped by the bundle port 4053 after passing through here and then enter the outlet pressure plate 404. A temperature sensor 406 and a downflow hole 4026 connected to the outlet position of the longitudinal S-shaped impregnation channel 4021 are provided at the bottom of the mold body 402, and an upflow hole 4027 connected to the inlet position of the longitudinal S-shaped impregnation channel 4021 is provided at the upper part of the mold body 402. A top screw structure is also provided between the cover plate 401 and the mold body 402, and the top screw structure includes two outer top screw holes 4013 on the cover plate 401 and two corresponding inner top screw holes 4023 on the mold body 402.

[0037] A semi-enclosed slot positioning structure is provided between the mold body 402 and the cover plate 401, and the semi-enclosed slot positioning structure includes a semi-enclosed positioning groove 4024 provided on the surface of the mold body 402 around the longitudinal S-shaped impregnation flow channel 4021 and a positioning convex strip 4011 provided on the cover plate 401 and matching with the positioning groove 4024. The bolt connection structure between the cover plate 401 and the mold body 402 includes a bolt connection outer hole 4012 on the cover plate 401 and a bolt connection inner hole 4025 on the mold body 402, the bolt connection outer holes 4012 are evenly arranged on the outside of the positioning convex strip 4011, and the bolt connection inner holes 4025 are arranged one by one on the outside of the positioning groove 4024. In this way, the matching connection of the positioning groove 4024 and the positioning convex strip 4011 can effectively prevent the melted material from flowing out along the gap between the cover plate 401 and the mold body 402 during the production process.

[0038] The sizing device 5 includes a sizing die 501, a heating sleeve 502, a fan 504 and an L-shaped bracket 503. The short side of the L-shaped bracket 503 is fixed on the cross bar 205, the fan 504 is installed at the lower part of the long side of the L-shaped bracket 503, the heating sleeve 502 is fixed at the upper part of the long side of the L-shaped bracket 503, the sizing die 501 is fixed in the middle of the heating sleeve 502, and the upper part of the long side of the L-shaped bracket 503 is provided with a corresponding die head avoidance area. A heating rod 507 and a temperature sensor 506 are installed on the heating sleeve 502. The heating rod 507 is installed below the sizing die 501, and the temperature sensor 506 is installed above the sizing die 501. By setting up this structure, the temperature of the heating sleeve 502 will not affect the bottom of the L-shaped bracket 503 when the impregnated continuous fiber passes through the sizing die 501 for sizing. This can ensure that the die hole height of the sizing die 501 remains basically unchanged, and prevent thermal expansion and contraction from affecting the die hole height of the sizing die 501 and causing the continuous fiber line diameter to change.

[0039] The winding device 7 includes a linear module 704, a stepper motor 701, a winding disk 702 and a pressure block 703. The linear module 704 is fixed on the winding seat 2015. The stepper motor 701 is installed on the linear module 704 and can move horizontally under the drive of the linear module 704. A transmission rod is installed at the power output end of the stepper motor 701. The winding disk 702 is installed on the transmission rod. The pressure block 703 is installed at the top of the transmission rod to fix the winding disk 702 on the transmission rod. In this way, the position of the linear module 704 can be adjusted as needed during actual winding, so that the continuous fiber can enter the winding disk 702 at a suitable angle.

[0040] In actual operation of this embodiment: the continuous fiber is drawn out from the continuous fiber drum 1, first oriented by the first guide wheel, then adjusted in tension by the tension adjustment wheel group consisting of the second guide wheel and two tension wheels, and then guided vertically downward by the third guide wheel, and enters into the impregnation mold 4 below through the sizing inlet hole on the inlet pressure plate 407, and after the surface is impregnated with plastic melt under high temperature conditions, it is drawn out in the horizontal direction through the sizing outlet hole of the outlet pressure plate 404 of the impregnation mold 4, and before the plastic on the surface is completely solidified, it passes through the heated sizing mold 501, and is constrained by the mold hole to keep the overall diameter of the pre-impregnated continuous fiber consistent, and finally is wound up by the winding device 7 after cooling and two times of guiding and tension adjustment. The most critical part in this embodiment is that during the impregnation process, the impregnation mold 4 adopts a longitudinal S-shaped impregnation channel 4021 composed of two bends. When the continuous fiber filament runs in the longitudinal S-shaped impregnation channel 4021, the surface tension of the continuous fiber changes once every bend due to the change in force direction, causing the micropores on the fiber surface to deform and extrude, forming a microscopic adsorption effect, so that the impregnation liquid can penetrate into the interior of the continuous fiber. Compared with the traditional roller pressure impregnation method, the impregnation depth is significantly increased, and the performance of the final product is also significantly enhanced.

[0041] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A continuous fiber prepreg production line for 3D printing, characterized in that: The continuous fiber prepreg production line comprises: a single screw extruder, a prepreg workbench, an impregnation die, a sizing device and a winding device. A pay-off frame, a pay-off guide frame, a die mounting position, a sizing position and a winding seat are arranged on the table of the prepreg workbench in sequence according to the running direction of the continuous fiber. The impregnation die is mounted on the die mounting position, the sizing device is mounted on the sizing position, the winding device is mounted on the winding seat, a plurality of guide wheels are mounted on the pay-off guide frame, which can guide the pay-off direction according to the requirements of the production line, and the impregnation die is mounted on the winding seat. A longitudinal S-shaped impregnation channel is provided in the tool. When the impregnation mold is fixed on the mold mounting position, the discharge port of the single-screw extruder is connected to the impregnation mold, so that the molten thermoplastic resin material can be extruded into the longitudinal S-shaped impregnation channel; the barrel of continuous fiber is placed on the pay-off frame, and the continuous fiber led out from the barrel is guided into the impregnation mold by the guide wheel on the pay-off guide frame, and is led out from the outlet of the impregnation mold after being impregnated in the longitudinal S-shaped impregnation channel, and is then wound up by the winding device after being sizing treated by the sizing device.

2. The continuous fiber prepreg production line for 3D printing according to claim 1, characterized in that: The prepreg workbench as a whole is a frame structure made of aluminum alloy profiles with mounting rails of the same specifications on four sides, including a workbench table, a wire pay-off frame and a wire pay-off guide frame. The workbench table is a rectangular frame formed by vertically splicing two long side columns of the same length and two short side columns of the same length. A plurality of load-bearing beams parallel to the short side columns are installed in the middle of the rectangular frame, and the four corners of the table are respectively installed with adjustable height foot columns; The pay-off rack comprises a pay-off support and a pay-off rod, wherein the pay-off support is vertically fixed at the middle position of the inner long side column, and the pay-off rod is vertically fixed on the pay-off support, and the fixing direction of the pay-off rod is parallel to the load-bearing beam; The pay-off guide frame comprises a first guide column, a second guide column and a guide beam, the first guide column and the second guide column have the same height, the second guide column is vertically fixed to a short side column on one side, the first guide column is fixed to a load-bearing beam close to the pay-off support column, a cooling fan is installed on the column body of the first guide column, the cooling fan faces the winding path of the continuous fiber, the guide beam is fixed to the top of the first guide column and the second guide column, a first guide wheel seat and a second guide wheel seat arranged in sequence along the pay-off direction are arranged on the beam body of the guide beam, a first guide wheel is installed on the first guide wheel seat, a second guide wheel is installed on the second guide wheel seat, two tension wheels are installed on the beam body on both sides of the second guide wheel seat, the second guide wheel and the two tension wheels together form a tension adjustment wheel group, the left end portion of the guide beam exceeds the end of the first guide column, and the exceeding portion is installed with a third guide wheel; The mold mounting position is arranged in the middle position of the second guide column, and a mold mounting plate is installed on the mold mounting position. When the impregnation mold is fixed on the mold mounting plate, the impregnation mold is located as a whole on the outside of the prepreg workbench table. The winding seat is arranged at the other end away from the mold mounting position, and the sizing position is arranged between the second guide column and the first guide column.

3. The 3D printing continuous fiber prepreg production line according to claim 2, characterized in that: The short side column directly below the impregnation mold is connected to the winding seat through a cross bar parallel to the long side column, the inner side of the cross bar is attached to the outer sides of the first guide column and the second guide column, and the sizing position is arranged on the cross bar and is located between the first guide column and the second guide column.

4. The continuous fiber prepreg production line according to claim 2, characterized in that: A wire-winding adjustment structure is also provided between the sizing position and the winding seat, and the wire-winding adjustment structure consists of two adjustment rods fixed in parallel on the work surface between the first guide column and the winding seat, namely the first adjustment rod and the second adjustment rod. The first adjustment rod and the second adjustment rod are coplanar with the wire-releasing guide frame, the first adjustment rod is installed with a fourth guide wheel, and the second adjustment rod is installed with a fifth guide wheel.

5. The 3D printing continuous fiber prepreg production line according to claim 1, characterized in that: A barrel seat is provided directly below the mounting position of the mold, and the barrel seat is fixed outside the prepreg workbench and is located below the table top.

6. The 3D printing continuous fiber prepreg production line according to claim 1, characterized in that: The impregnation mold includes a cover plate, a mold body, a heating plate, an inlet pressure plate and an outlet pressure plate. The cover plate and the heating plate have the same size as the mold body. The cover plate is pressed tightly on the surface of the mold body by fastening bolts. The heating plate is fixed to the back of the mold body by fastening bolts. A longitudinal S-shaped impregnation flow channel is provided on the surface of the mold body. The inlet and outlet directions of the longitudinal S-shaped impregnation flow channel are perpendicular and have at least two continuous turns. A feed hole is provided on one side of the mold body. A flange that can be connected to the head of the single-screw extruder is installed outside the feed hole. The feed hole penetrates into the mold. The lower half of the longitudinal S-shaped immersion channel is connected to the body, and an inlet pressure plate and an outlet pressure plate are respectively installed at the inlet and outlet of the longitudinal S-shaped immersion channel. The inlet pressure plate is provided with a sizing inlet hole, and the outlet pressure plate is provided with a sizing outlet hole. A temperature sensor and a downflow hole connected to the outlet position of the longitudinal S-shaped immersion channel are provided at the bottom of the mold body. An upflow hole connected to the inlet position of the longitudinal S-shaped immersion channel is provided on the upper part of the mold body. A top screw structure is also provided between the cover plate and the mold body, and the top screw structure includes an outer top screw hole on the cover plate and a corresponding inner top screw hole on the mold body.

7. The 3D printing continuous fiber prepreg production line according to claim 1, characterized in that: A semi-enclosed card slot positioning structure is provided between the mold body and the cover plate, and the bolt connection structure between the cover plate and the mold body is evenly arranged on the outside of the semi-enclosed card slot positioning structure. The semi-enclosed card slot positioning structure includes a semi-enclosed positioning groove arranged on the surface of the mold body around the longitudinal S-shaped immersion channel and a positioning convex strip arranged on the cover plate and matching the positioning groove.

8. The 3D printing continuous fiber prepreg production line according to claim 1, characterized in that: A V-shaped positioning pin is installed at the outlet position of the longitudinal S-shaped impregnation flow channel. The V-shaped positioning pin consists of a pin rod and a pin head. A V-shaped material bundling port is arranged between the pin rod and the pin head.

9. The 3D printing continuous fiber prepreg production line according to claim 1, characterized in that: The sizing die comprises a sizing die, a heating sleeve, a fan and an L-shaped bracket, the short side of the L-shaped bracket is fixed on the cross bar, the fan is installed at the lower part of the long side of the L-shaped bracket, the heating sleeve is fixed at the upper part of the long side of the L-shaped bracket, the sizing die is fixed in the middle of the heating sleeve, the upper part of the long side of the L-shaped bracket is provided with a corresponding die head avoidance area, a heating rod and a temperature sensor are installed on the heating sleeve, the heating rod is installed below the sizing die, and the temperature sensor is installed above the sizing die.

10. The 3D printing continuous fiber prepreg production line according to claim 1, characterized in that: The winding device includes a linear module, a stepper motor, a winding disk and a pressure block. The linear module is fixed on the winding seat. The stepper motor is installed on the linear module and can move horizontally under the drive of the linear module. A transmission rod is installed at the power output end of the stepper motor. The winding disc is installed on the transmission rod, and the pressing block is installed on the top end of the transmission rod to fix the winding disc on the transmission rod.

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